Balance weight for pianoforte keys and the like



Oct. 7 1 24- w. FINNIMORE BALANCE WEIGHT FOR PIANOFORTE KEYS AND THE LIKE Filed Feb. 20, 1924 W? I harm Patented Oct. 7, 1924.

UNITED STATES WILLIAM FINNIMORE, OF LONDON, ENGLAND.

BALANCE WEIGHT FOR PIANO'FORTE KEYS AND THE LIKE.

Application filed February 20, 1924. Serial No. 694,111.

To all whom it may concern:

Be 1t known that I, WILLIAM FINNIMORE,

a subject of the King of England, residing at London, England, have invented new and 5 useful Improvements in Balance WVeights for Pianoforte Keys and the like, of which the following is a specification.

In order to counterbalance a pianoforte key, it is usual to drill a hole in the rear end ofthe same and fill such hole with lead.

This method is a crude one and has the disadvantage that the lead, owing to the shrinking of the wood, is liable to get loose and hinder the key in its movement. Moreover, damage to the material is often causedby the splitting of the wood when the hole is drilled or filled, and overlooked splinters, shavings and cores, may cause friction.

It has also been proposed to balance pianoforte and like keys by means of a slotted metal block which is guided by pins in a groove in the key so that it can be adjusted along the latter and secured in adjusted position by means of a screw passing through the slot in the block.

The object of the present invention is to employ a balancing weight in combination with the rod which transmits the motion of the key to the action of the instrument, in such a manner that the two elements will mutually control one another and allow of being fixed by one screw and in a single operation. With this object in view an elongatedbalancing weight of soft metal is formed with a screw-hole and with a plurali ty of apertures in which to receive and grip the milled lower end of the motion-transmitting rod, the latter being adapted to pass through the block into the key so as to prevent a rotary displacement of the block about the screw whereby both elements are secured in position. This arrangement allows the position of the block'on the key to be varied while the rod, by being inserted in the most favorably situated aperture in the block, will remain in its normal position relative to the piano action. Intermediate adjustments may be effected by a shortening of the block, for which purpose the latter is notched so that small portions of the same can easily be nipped off.

By this arrangement the fitting up and balancing of the keys will be greatly facilitated, while the mechanism will gain considerably in appearance.

block.

Fig. l of the accompanying drawings rep resents a side view of the device,

Fig. 2, an end view, and

Fig. 3, a plan of the same.

Fig. 4 shows the device applied to a key.

The device is composed of a metal block a which is screwed onto the top of the key I) and adapted to hold the rod 0 wherebythe 'movement of the key is transmitted to the action d, say, of a piano. The rod 0 is formed with a milled or fluted lower portion which is driven through a socket in the block and which enters the key I) so as to hold the block in position on the latter- Thus a single screw 6 will suffice for fastening the block to the key. The block has an aperture f for the reception of the screw 6, the milled portion of the rod 0 cuts into the block and forms a rigid connection, while rotary dis placement of the rod is prevented.

Incisions g are made in the far end of the block. so that small portions can easily be nipped off in order to reduce the weight, should it be required for obtaining a delicate adjustment of the balance. To allow a greater scope of adjustment, the block may be provided with a plurality of sockets for the reception of the rod 0. Vith this arrangement the balance can be regulated for varying the distance of the block from the fulcrum of the key, the block being arranged with the most suitably situated socket in position to receive the rod 0. Intermediate adjustment can be effected by a shortening of the block, as previously described.

The sockets for the rod 0 may be made in a raised portion or portions h of the block so that a long contact surface is obtained by which the rod will be rigidly supported.

The block is preferably cast out of soft 9 metal.

I claim 1. In a pianoforte or like key, the combination with a motion-transmitting rod, of a metal block for balancing the key, said rod being driven through the block into the key so that it will hold the block in position with the aid of a single fastening screw and so that it will itself be held in position by the 2. In a pianoforte or like key, the combination with a motion-transmitting rod, of a metal block for balancing the key, said rod being driven through the block into the key so that it will hold the block in position with the aid of a single fastening screw and so that it will itself be held in position by the block, the block being provided with a plurality of apertures for the reception of the rod so that the position of the block on the key can be varied Without varying the position of the rod relative to the same.

3. In a pianoforte or like key, the co1nbination With a motion-transmitting rod, of a metal block for balancing the key, said rod being driven through the block into the key, so that it Will hold the block in position With the aid of a single fastening screw and so that it Will itself be held in position by the block, the block being provided with a plurality of apertures for the reception of the rod so that the position of the block on the key can be varied Without varying the position of the rod relative to the same the end of the rod being milled for engagement with the block apertures.

41-. In a pianoforte or like key, the combination with a motion-transmitting rod, of a metal block for balancing the key, said rod being driven through the block into the key so that it will hold the block in position With the aid of a single fastening screw and so that it will itself be held in position by the block, the block being provided With a plurality of apertures for the reception of the rod so that the position of the block on the key can be Varied Without varying the position of the rod relative to the same, the block being notched at one end to allow portions of the same to be easily broken oil for further regulation of the balance.

WILLIAM FINNIMORE. 

